+ Refactor ExpansionInfo.CurrentExpansion to ExpansionInfo.CoreExpansion.
+ Add HousingFlags enum for more intuitive use when defining expansions.
+ Corrected housing flags values;
* I may be wrong, but the comments suggest that the OR'd flags are not actually equal to the values used when defining custom housing flags in each expansion. The defined values seem to indecate that a mixture of CharacterListFlags and FeatureFlags were used - possibly as a mistake.
